This invention relates to a construction of a contrasting marker panel for highway guardrails and the like, and a method of forming the same. More particularly, this invention relates to a marker panel which may be mounted preferably totally within the generally longitudinally extending and generally U-shaped cross section recess of conventional highway guardrails so that the front surface of the marker panel within the guardrail recess is exposed transversely of highway traffic flow. Furthermore, certain contrasting surface portions in the form of colors and/or reflectorized surface portions are provided on the marker panel which are exposed outwardly of the guardrail recess to thereby form a contrasting indication of the guardrail marked highway limits fully visible against highway surrounding background to vehicles traveling the adjacent highway.
The use of longitudinally continuous guardrails along highways including centrally of the highways for separating oppositely flowing traffic thereon in modern highway design is quite well known. Such use is particularly frequent in and around urban areas due to greatly increased traffic congestion and vehicle intensity in order to maximize travel safety. Furthermore, in the case of freeways and turnpikes, the use of continuous guardrails is almost an absolute necessity.
Probably the most commonly used form of continuous guardrail is that formed of sheet iron or steel contoured with longitudinally continuous and somewhat arcuately formed upper and lower projections vertically separated by a somewhat U-shaped recess. These metal guardrails are supported on spaced, usually wooden, supporting posts and are quite effective in reasonably resisting penetration by vehicles, particularly when contacted at an angular or somewhat glancing force. With the particular contouring of these guardrails, not only can the guardrails be formed relatively strong without the use of prohibitive metal thicknesses, but the somewhat smooth contour thereof tends to redirect a vehicle contacting the same back onto the adjacent highway in many cases with far lesser damage to the vehicle than has been possible with common barrier posts with cable reinforcing and the like.
It is also well known in modern highway design to make increasingly more frequent use of various types of markers, sometimes including reflectors, in order to increase directional visibility for the vehicle drivers by providing a discernible contrast between the highway and the adjacent land areas. The use of such reflectors is particularly effective during night hours where there is a minimum amount of light for visibility and become even more valuable during rainy and otherwise inclement weather conditions where normal visibility is minimal. For instance, there is presently quite extensive use, particularly on freeways and turnpikes where speeds of vehicles are in the higher ranges, of reflectorized traffic lane marking wherein reflectorized pads are mounted at spaced locations along and aligned with the traffic lane stripes which not only provide increased visibility for a vehicle driver in order that such driver may maintain his vehicle properly aligned with a given traffic lane, but upon the vehicle moving out of its particular traffic lane, the vehicle passing over the reflectorized pads gives a noise indication that the vehicle has assumed such directional movement from a given traffic lane.
In order to even further enhance this reflectorization concept relative to highway design and provide even increased vehicle safety for further reducing both property damage and human injury, it has become highly desirable to provide equivalent reflectorized marking of the side highway guardrails. In this manner, not only will the vehicle lanes with their present reflectorized marking be more clearly visible during night and inclement weather conditions, but the side limits of the highways will be equally as well marked and visible so that the vehicle drivers may remain at all times more fully oriented as to approaching directional changes of the highways. With the reflectors picking up and reflecting minimum light at quite extensive distances, the pattern of the path of the highway is quite apparent to the vehicle driver at quite great distances even under the minimum light conditions and at the present-day vehicle speeds so that approaching highway directional conditions are more clearly apparent to the vehicle driver and can be more easily anticipated.
The reflectorization of the highway guardrails has, however, presented certain basic difficulties. Keeping in mind that the above-described metal guardrails are deliberately designed to present a relatively smooth surface for a vehicle contacting the same in order to minimize damage to the vehicle and ultimately to its occupants, it becomes a problem as to just how to mount reflectors thereon without partially destroying the guardrail smooth attributes. Furthermore, since the guardrails are at the sides of the highway so as to be spaced transversely from the normal vehicle longitudinal flow, reflectors mounted flatwise merely against the guardrail surfaces will only have a minimal effect of collecting and reflecting light from and to the vehicles traveling the highway lanes.